Is this carbon buildup? And how can I fix this?
Oh hell. Look at this.
Looks like vacuum advance is connected to manifold vacuum. Red arrows. In many cases that can lead to too much timing at idle.
And the port for the vacuum advance timing is capped. Yellow arrow. The cap is dried out and cracked too. H'mm.
Anyway if I'm right, what you do after the first test is take the golf tee out and reconnect the hose. Then remeasure rpm and timing. You'll probbaly see a big jump in both :( But who knows so check it out. Proper way to set initial is with vac advance plugged. Then in most cases with a stock distributor, connect to the timing port (yellow arrow) and cap the manifold vac port.
Also not seeing PCV. That also can effect idle.
Oh hell. Look at this.
Looks like vacuum advance is connected to manifold vacuum. Red arrows. In many cases that can lead to too much timing at idle.
And the port for the vacuum advance timing is capped. Yellow arrow. The cap is dried out and cracked too. H'mm.
Anyway if I'm right, what you do after the first test is take the golf tee out and reconnect the hose. Then remeasure rpm and timing. You'll probbaly see a big jump in both :( But who knows so check it out. Proper way to set initial is with vac advance plugged. Then in most cases with a stock distributor, connect to the timing port (yellow arrow) and cap the manifold vac port.
Also not seeing PCV. That also can effect idle.
